iwlwifi: mvm: change state when queueing agg start work

Add a new state to enum iwl_mvm_agg_state, which is used between
queueing the work that starts tx aggregations and actually starting that
work (changing to state IWL_AGG_STARTING).
This solves a race where ieee80211_start_tx_ba_session is called a
second time, before the work queued by the first run has a chance to
change the agg_state. In this case the second call to
ieee80211_start_tx_ba_session returns an error, and the fallback is to
abort the ba session start.

Fixes: 482e48440a0e ("iwlwifi: mvm: change open and close criteria of a BA session")
Signed-off-by: Naftali Goldstein <naftali.goldstein@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index 411a205..2dafe9b 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -2385,8 +2385,10 @@ int iwl_mvm_sta_tx_agg_start(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 	if (WARN_ON_ONCE(tid >= IWL_MAX_TID_COUNT))
 		return -EINVAL;
 
-	if (mvmsta->tid_data[tid].state != IWL_AGG_OFF) {
-		IWL_ERR(mvm, "Start AGG when state is not IWL_AGG_OFF %d!\n",
+	if (mvmsta->tid_data[tid].state != IWL_AGG_QUEUED &&
+	    mvmsta->tid_data[tid].state != IWL_AGG_OFF) {
+		IWL_ERR(mvm,
+			"Start AGG when state is not IWL_AGG_QUEUED or IWL_AGG_OFF %d!\n",
 			mvmsta->tid_data[tid].state);
 		return -ENXIO;
 	}